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Cadmium (Cd) pollution is a global environmental problem. It is of great significance to find a kind of pasture that can grow normally in a cadmium environment, especially in the Tibetan Plateau. We studied the fruit germination and fruit growth of Elymus sinsubmuticus S.L. Chen and Elymus tangutorum (Nevski), native plants of the Tibetan Plateau, in different cadmium environments. The results showed that with increased cadmium stress, the fruit germination rate, final germination rate, fruit-vigor, average germination time, and germination-speed index for the two grass species gradually decreased, and the 50% germination time for the seed gradually increased. Root length, biomass, and the number of leaves decreased in both species. We quantified the fruit germination and growth of plants in the cadmium environment and found that E. sinosubmuticus S.L. Chen had better fruit germination and fruit growth, and it had the development potential of cadmium pollution control.

With the development of steel-structure construction technology in high-rise buildings, the design and construction of high-rise steel structures tend to be complicated. Based on the Zhuhai Tiejian Square project, the fluid-structure coupling calculation analysis and on-site monitoring are carried out in view of the wind load of the high-altitude steel-structure connecting bridge in the hoisting stage of the Zhuhai Tiejian Square project. The main structure of the project is four towers and five high-altitude, small-spacing steel structures connecting the four towers. The lifting process of the third zone is taken as the analysis object, and the hoisting idea of "low-altitude hoisting, overall lifting" is adopted. Because the span of the high-altitude steel-structure connecting bridge is small and the installation height is high, the influence of wind load on the hoisting process cannot be ignored. Therefore, the unidirectional fluid-structure coupling model of the high-altitude small-space steel-structure connecting bridge in the third zone was established by using CFD calculation software ANSYS Fluent 2022 R1, and the corresponding flow field and solid calculation results were obtained and analyzed. The analysis results show that the lifting structure still produces a certain deformation when the wind speed is 5 m/s or 10 m/s, and the calculation results show that the stress calculation results are still within the safe range of steel strength for the sensitivity of the lifting structure under wind load. With the increase of wind speed, the local maximum stress of the structure increases greatly, but the overall deformation remains stable, which indicates that the greatest challenge of hoisting steel structures under wind load may be the stability direction rather than the strength, so it is necessary to strictly monitor the displacement deformation of the structure during construction. Then, through the monitoring of the overall lifting process of the high-altitude, large-span, steel-connected structure of Zhuhai Tiejian Square from pre-lifting to formal lifting, real-time monitoring and data analysis show that the lifting process of the high-altitude steel bridge of Zhuhai Tiejian Square is safe and reliable, the force transformation of each component is reasonable, the lifting process is relatively stable, the external environment has little impact, and the expected monitoring effect has been achieved. The calculation simulation and on-site monitoring in this paper can provide theoretical and practical guidance for the construction safety under the influence of wind load in the construction process of high-altitude steel-structure hoisting, and provide an important reference value for similar projects. [ABSTRACT FROM AUTHOR]

Nanomaterials (NMs) are becoming more commonly used in microalgal biotechnology to empower the production of algal biomass and valuable metabolites, such as lipids, proteins, and exopolysaccharides. It provides an effective and promising supplement to the existing algal biotechnology. In this review, the potential for NMs to enhance microalgal growth by improving photosynthetic utilization efficiency and removing reactive oxygen species is first summarized. Then, their positive roles in accumulation, bioactivity modification, and extraction of valuable microalgal metabolites are presented. After the application of NMs in microalgae cultivation, the extracted metabolites, particularly exopolysaccharides, contain trace amounts of NM residues, and thus, the impact of these residues on the functional properties of the metabolites is also evaluated. Finally, the methods for removing NM residues from the extracted metabolites are summarized. This review provides insights into the application of nanotechnology for sustainable production of valuable metabolites in microalgae and will contribute useful information for ongoing and future practice. [ABSTRACT FROM AUTHOR]

Summary: Marine planktonic diatoms are among the most important contributors to phytoplankton blooms and marine net primary production. Their ecological success has been attributed to their ability to rapidly respond to changing environmental conditions.Here, we report common molecular mechanisms used by the model marine diatom Thalassiosira pseudonana to respond to 10 diverse environmental stressors using RNA‐Seq analysis.We identify a specific subset of 1076 genes that are differentially expressed in response to stressors that induce an imbalance between energy or resource supply and metabolic capacity, which we termed the diatom environmental stress response (d‐ESR). The d‐ESR is primarily composed of genes that maintain proteome homeostasis and primary metabolism. Photosynthesis is strongly regulated in response to environmental stressors but chloroplast‐encoded genes were predominantly upregulated while the nuclear‐encoded genes were mostly downregulated in response to low light and high temperature.In aggregate, these results provide insight into the molecular mechanisms used by diatoms to respond to a range of environmental perturbations and the unique role of the chloroplast in managing environmental stress in diatoms. This study facilitates our understanding of the molecular mechanisms underpinning the ecological success of diatoms in the ocean. [ABSTRACT FROM AUTHOR]

Currently, n‐type small‐molecule mixed ionic‐electronic conductors remain less explored and their molecular design rules are not mature enough. Herein, two n‐type glycolated imide‐fused polycyclic aromatic hydrocarbons (IPAHs), d‐gdiPDI and t‐gdiPDI, are developed to probe the effects of molecular conformation on the electronic, electrochemical, morphological, and coupled ionic‐electronic transport properties. It is found that the highly twisted scaffold in d‐gdiPDI, compared to the nearly planar one of t‐gdiPDI, has a strong positive effect on the charge storage properties and thus the performance of organic electrochemical transistors (OECTs). d‐gdiPDI exhibits a volumetric capacitance of 657 F cm−3, obviously outperforming that of t‐gdiPDI (261 F cm−3), which is the highest value reported to date for small‐molecule OECT materials. Moreover, a high charge‐storage capacity of up to 479 F g−1 is observed for d‐gdiPDI. Arising from such high ionic‐electronic coupling characteristic, d‐gdiPDI‐based OECTs present a ≈2 × times higher geometry‐normalized transconductance (gm,norm) of 105.3 mS cm−1 relative to that of t‐gdiPDI counterparts. Significantly, further application of d‐gdiPDI in solid‐electrolyte OECTs delivers a gm,norm of 142.4 mS cm−1. These findings indicate that IPAHs are very promising candidates for n‐type small‐molecule OECTs and highlight the superiority of twisting conformation manipulation in materials design toward high‐performance electrochemical devices. [ABSTRACT FROM AUTHOR]

Global climate change leads to simultaneous changes in multiple environmental drivers in the marine realm. Although physiological characterization of coccolithophores has been studied under climate change, there is limited knowledge on the biochemical responses of this biogeochemically important phytoplankton group to changing multiple environmental drivers. Here, we investigate the interactive effects of reduced phosphorus availability (4 to 0.4 µ mol L -1) , elevated pCO 2 concentrations (426 to 946 µ atm), and increasing light intensity (40 to 300 µ mol photons m -2 s -1) on elemental content and macromolecules of the cosmopolitan coccolithophore Emiliania huxleyi. Reduced phosphorus availability reduces particulate organic nitrogen (PON) and protein contents per cell under 40 µ mol photons m -2 s -1 but not under 300 µ mol photons m -2 s -1. Reduced phosphorus availability and elevated pCO 2 concentrations act synergistically to increase particulate organic carbon (POC) and carbohydrate contents per cell under 300 µ mol photons m -2 s -1 but not under 40 µ mol photons m -2 s -1. Reduced phosphorus availability, elevated pCO 2 concentrations, and increasing light intensity act synergistically to increase the allocation of POC to carbohydrates. Under elevated pCO 2 concentrations and increasing light intensity, enhanced carbon fixation could increase carbon storage in the phosphorus-limited regions of the oceans where E. huxleyi dominates the phytoplankton assemblages. In each type of light intensity, elemental-carbon-to-phosphorus (C:P) and nitrogen-to-phosphorus (N:P) ratios decrease with increasing growth rate. These results suggest that coccolithophores could reallocate chemical elements and energy to synthesize macromolecules efficiently, which allows them to regulate their elemental content and growth rate to acclimate to changing environmental conditions. [ABSTRACT FROM AUTHOR]

In the development of high‐performance organic thermoelectric devices, n‐type materials, especially with small molecule semiconductors, lags far behind p‐type materials. In this paper, three small molecules are synthesized based on electron‐deficient naphthalene bis‐isatin building blocks bearing different alkyl chains with the terminal functionalized with 3‐ethylrhodanine unit and studied their aggregation and doping mechanism in detail. It is found that crystallinity plays an essential role in tuning the doping behavior of small molecules. Molecules with too strong crystallinity tend to aggregate with each other to form large crystalline domains, which cause significant performance degradation. While molecules with weak crystallinity can tolerate more dopants, most of them exhibit low mobility. By tuning the crystallinity carefully, organic thermoelectric devices based on C12NR can maintain high mobility and realize effective doping simultaneously, and a high power factor of 1.07 µW m−1 K−2 at 100 °C is realized. This delicate molecular design by modulating crystallinity provides a new avenue for realizing high‐performance organic thermoelectric devices. [ABSTRACT FROM AUTHOR]

The primary challenge for n‐type small‐molecule organic electrochemical transistors (OECTs) is to improve their electron mobilities and thus the key figure of merit μC*. Nevertheless, few reports in OECTs have specially proposed to address this issue. Herein, we report a 10‐ring‐fused polycyclic π‐system consisting of the core of naphthalene bis‐isatin dimer and the terminal moieties of rhodanine, which features intramolecular noncovalent interactions, high π‐delocalization and strong electron‐deficient characteristics. We find that this extended π‐conjugated system using the ring fusion strategy displays improved electron mobilities up to 0.043 cm2 V−1 s−1 compared to our previously reported small molecule gNR, and thereby leads to a remarkable μC* of 10.3 F cm−1 V−1 s−1 in n‐type OECTs, which is the highest value reported to date for small‐molecule OECTs. This work highlights the importance of π‐conjugation extension in polycyclic‐fused molecules for enhancing the performance of n‐type small‐molecule OECTs. [ABSTRACT FROM AUTHOR]

Global climate change leads to simultaneous changes in multiple environmental drivers in the marine realm. Although physiological characterization of coccolithophores have been studied under climate change, there is limited knowledge on the biochemical responses of this biogeochemically important phytoplankton group to changing multiple environmental drivers. Here we investigate the interactive effects of reduced phosphorus availability (4 to 0.4 μmol L–1), elevated p CO2 concentrations (426 to 946 μatm) and increasing light intensity (40 to 300 μmol photons m–2 s–1) on elemental content and macromolecules of the cosmopolitan coccolithophore Emiliania huxleyi. Reduced phosphorus availability reduces particulate organic nitrogen and protein contents under low light intensity, but not under high light intensity. Reduced phosphorus availability and ocean acidification act synergistically to increase particulate organic carbon (POC) and carbohydrate contents under high light intensity but not under low light intensity. Reduced phosphorus availability, ocean acidification and increasing light intensity act synergistically to increase the allocation of POC to carbohydrates. Under future ocean acidification and increasing light intensity, enhanced carbon fixation could increase carbon storage in the phosphorus-limited regions of the oceans where E. huxleyi dominates the phytoplankton assemblages. In each light intensity, elemental carbon to phosphorus (C : P) and nitrogen to phosphorus (N : P) ratios decrease with increasing growth rate. These results suggest that coccolithophores could reallocate chemical elements and energy to synthesize macromolecules efficiently, which allows them to regulate its elemental content and growth rate to acclimate to changing environmental conditions. [ABSTRACT FROM AUTHOR]

Highly efficient mixed ionic and electronic conduction is critical to developing high‐performance organic electrochemical transistors (OECTs) devices. While currently, the n‐type small molecules mixed conductors design strategy remains extremely lacking. Herein, ethylene glycol (EG) chain substituted electron‐deficient naphthalene bis‐isatin and rhodanine acceptor units with easily accessible steps are rationally fused, affording fused and planar novel semiconductors with weak intramolecular S–O 'conformation locks', where gNR with EG side chain and hgNR with hybrid alkyl‐EG side chain. The rigid, planar and highly electron‐deficient skeleton enables the resulting small molecule semiconductors to be efficient mixed ionic‐electronic conductors with very high OECT electron mobility up to 0.01 cm2 V−1 s−1. Remarkedly, gNR displays the record value of geometry‐normalized transconductance of 0.4 S cm−1 and μC* of 2.6 F V−1 cm−1 s−1, which can also be compared with the state‐of‐art n‐type semiconducting polymers in OECTs. Moreover, the effect of the alkyl spacer on the n‐type mixed ionic and electronic conduction features of the small molecule materials is investigated. The fused electron‐deficient acceptor‐acceptor (A–A) system with intramolecular conformation lock design strategy in this work provides a new avenue to realize next‐generation high‐performance small molecule mixed ionic and electronic conductors for OECT materials. [ABSTRACT FROM AUTHOR]

In this paper, five groups of industrial aluminium back-surface-field (Al-BSF) solar cells were made from silicon wafers from different locations of a B-doped Czochralski silicon ingot. Then, we performed the first LID (45 °C, 1 sun, 12 h), regeneration (100 °C, 1 sun, 24 h), and second LID (45 °C, 1 sun, 12 h) treatments on the cells, and measured the in-situ changes of their I-V characteristic parameters by using an I-V tester during the experiment. The cells were also characterized by Suns-Voc measurement, full-area light beam induced current scanning, and external quantum efficiency measurement at the four breakpoints of treatments (before and after the first LID, after regeneration and the second LID). It was found that the LID and regeneration of the Al-BSF solar cells can be explained by the LID and regeneration reaction of B-O defects and the LID caused by dissociation of Fe-B pairs. After regeneration, the relative decay rate of efficiency decreased from 2.75–3.8% during the first LID to 0.42–1.23% during the second LID, indicating that regeneration treatment (100 °C, 1 sun, 24 h) can improve the anti-LID ability of Al-BSF solar cells. [ABSTRACT FROM AUTHOR]

In this work, three n‐type donor–acceptor copolymers consisting of glycolated naphthalene tetracarboxylicdiimide (gNDI) coupled with variable donating companion moieties are reported. Using 2,2′‐bis(3,4‐ethylenedioxy)bithiophene, 2,​2′‐​bithiophene, 3,3′‐difluoro‐2,2′‐bithiophene (FBT), the donating strength of the donor units is systematically functionalized. These copolymers are used as a platform for aqueous‐based electrochemical devices, including energy‐storage devices, electrochromic devices (ECDs), and organic electrochemical transistors (OECTs). It is found that the electrochemical redox stability and electron mobility of copolymers are significantly improved via weakening the electron‐donating strength of donor units. gNDI coupling with FBT (gNDI‐FBT) exhibits a charge‐storage capacity exceeding 190 Fg−1, which is the highest value reported to date for NDI‐based polymer electrodes in aqueous media. For ECDs, gNDI‐FBT remains 100% of initial electrochromism contrast (∆%T = 20%) up to 1200 s. In addition, gNDI‐FBT outperforms its two analogs in OECTs, including lower threshold voltage (0.19 V), faster response time (45.5 ms), and higher volumetric capacitance (197 F cm−3). Moreover, gNDI‐FBT with fluorine atoms leads to the bipolarons delocalization along the polymer backbone and favorable molecular packing for ion–electron transport. Through such weak donor functionalization strategy, this work provides ways for n‐type copolymers tuning to access desirable performance metrics in optical, electrochemical, and bioelectronic applications. [ABSTRACT FROM AUTHOR]

Summary: Housekeeping genes (HKGs) are constitutively expressed with low variation across tissues/conditions. They are thought to be highly conserved and fundamental to cellular maintenance, with distinctive genomic features.Here, we identify 1505 HKGs in the unicellular marine diatom Thalassiosira pseudonana based on an RNA‐seq analysis of 232 samples taken under 12 experimental conditions over 0–72 h. We identify promising internal reference genes (IRGs) for T. pseudonana from the most stably expressed HKGs.A comparative analysis indicates < 18% of HKGs in T. pseudonana have orthologs in other eukaryotes, including other diatom species. Contrary to work on human tissues, T. pseudonana HKGs are longer than non‐HKGs, due to elongated introns. More ancient HKGs tend to be shorter than more recent HKGs, and expression levels of HKGs decrease more rapidly with gene length relative to non‐HKGs.Our results indicate that HKGs are highly variable across the tree of life and thus unlikely to be universally fundamental for cellular maintenance. We hypothesize that the distinct genomic features of HKGs of T. pseudonana may be a consequence of selection pressures associated with high expression and low variance across conditions. [ABSTRACT FROM AUTHOR]

As new and better materials are implemented for organic electrochemical transistors (OECTs), it becomes increasingly important to adopt more economic and environmentally friendly synthesis pathways with respect to conventional transition‐metal‐catalyzed polymerizations. Herein, a series of novel n‐type donor–acceptor‐conjugated polymers based on glycolated lactone and bis‐isatin units are reported. All the polymers are synthesized via green and metal‐free aldol polymerization. The strong electron‐deficient lactone‐building blocks provide low‐lying lowest unoccupied molecular orbital (LUMO) and the rigid backbone needed for efficient electron mobility up to 0.07 cm2 V−1 s−1. Instead, polar atoms in the backbone and ethylene glycol side chains contribute to the ionic conductivity. The resulting OECTs exhibit a normalized maximum transconductance gm,norm of 0.8 S cm−1 and a μC* of 6.7 F cm−1 V−1 s−1. Data on the microstructure show that such device performance originates from a unique porous morphology together with a highly disordered amorphous microstructure, leading to efficient ion‐to‐electron coupling. Overall, the design strategy provides an inexpensive and metal‐free polymerization route for high‐performing n‐type OECTs. [ABSTRACT FROM AUTHOR]